The label has a header. Should I enter this information somewhere?
You should only enter header information in the data entry form if it indicates that the plant was collected for a very special project, such as "Plants of Irrigation Canals". Do not include the full header if it only indicates the flora or a survey of a specific region, for example, "Plants of Joshua Tree National Park" or "Flora of Riverside County." For the first example, you would put just "Joshua Tree National Park" in the Locality field (as long as you aren't duplicating information that is listed elsewhere on the label). For the second example, you would select Riverside as the county, but nowhere do you need to indicate "Flora of Riverside County" verbatim.
You also do not need to enter header information if it indicates the name of an herbarium or specific collection. Be aware that the name of the collector is sometimes included in the name of the herbarium, but only rarely.